With a 1400 Mohm resistor across its terminals, the terminal voltage of a certain battery is 2.56V. With only a 5.04ohm resistor across its terminals, the terminal voltage is 1.72V.
(a) Find the internal emf of this battery.
(b) Find the internal resistance of this battery
(c) What would be the terminal voltage if the 5.04ohm resistor were replaced by a 7.04ohm resistor?